Cytochemical characterization of peripheral blood cell populations of two Cyprinidae,Carassius auratusandCtenopharyngodon idellus

Abstract

Fish are the most diverse species of all vertebrate groups, and their blood cells have shown variable characteristics in terms of morphology. Cytochemical staining for enzyme activity in blood leukocytes will help assess the immune function of fish. We characterize blood cells from crucian carp (Carassius auratus) and grass carp (Ctenopharyngodon idellus) by using a Diff‐Quick stain as well as different cytochemical methods. Blood specimens obtained from crucian carp and grass carp were evaluated after cytochemical staining for acid phosphatase (ACP), alkaline phosphatase (ALP), naphthol AS chloroacetate esterase (AS‐DNCE), naphthyl acetate esterase (NAE), α‐naphthyl butyrate esterase (NBE), peroxidase (MPO) and periodic acid–Schiff's reaction (PAS) using commercial kits. Blood cell types were evaluated based on their morphological characteristics and the presence or absence of specific chromogen. The expression pattern of enzymes was similar between the two Cyprinidae and was also broadly consistent with other fish species. However, there were some interesting differences detected between crucian carp and grass carp, including naphthol AS chloroacetate esterase activity in monocytes, peroxidase activity and location in thrombocytes. The ACP, ALP and MPO expressions of different leukocytes of the two Cyprinidae were evaluated by Image Pro Plus and were analysed for statistical significant differences. This investigation provides basic haematology and enzyme activity analyses for crucian carp and grass carp and serves as an approach to evaluating the immune response of fish.

Hematological and cytochemical characteristics of peripheral blood cells in the argus snakehead (Ophiocephalus argus Cantor)

“…We found a small number of immature erythrocytes in the peripheral blood of O. argus , which was consistent with reports in other fish. However, the morphology of immature erythrocytes in O. argus were round with a smaller and mostly-round nucleus, which was somewhat different from that of other fish, such as S. prenanti ( Fang et al, 2014 ), the spotted rose snapper ( Rio-Zaragoza et al, 2011 ), piebald naked carp ( Tang et al, 2015 ), crucian carp, and grass carp ( Zhang et al, 2019 ), whose immature erythrocytes were mostly ovoid or oval in shape, with a larger, elliptic nucleus.…”

“…Most fish have only eosinophils without basophils ( Gao et al, 2007b ; Milad et al, 2016 ; Motlagh et al, 2012 ; Rio-Zaragoza et al, 2011 ; Vázquez & Guerrero, 2007 ; Zheng et al, 2016 ). Few fish have only basophils without eosinophils ( Shigdar, Harford & Ward, 2009 ; Da Silva et al, 2011 ; Zhang et al, 2019 ), and some fish have neither eosinophils nor basophils ( Chen et al, 2019a ; Da Silva et al, 2011 ; Fang et al, 2014 ; Tavares-Dias & Moraes, 2004 ; Zhang et al, 2011 ). We did not find eosinophils and basophils in the peripheral blood of O. argus .…”

“…Traditional Wright’s staining can be used to study the microstructure and classification of fish blood cells ( Zhang et al, 2019 ). Cytochemical staining is commonly used to detect biological macromolecules and the activity of enzymes, and can improve our understanding of the function and physiological state of blood cells and cell lineages ( Massar et al, 2012 ; Shigdar, Harford & Ward, 2009 ).…”

“… Zheng et al (2016) investigated the ultrastructure and cytochemical properties of the peripheral blood cells of the piebald naked carp ( Gymnocypris eckloni ) by transmission electron microscopy. Zhang et al (2019) compared the microstructure and cytochemical characteristics of peripheral blood cells in the crucian carp ( Carassius auratus ) and grass carp ( Ctenpharyngodon idellus ). These studies indicated that the major groups and micromorphology of peripheral blood cells in different fish were generally similar.…”

Molecular characterization and functional analysis of interferon regulatory factor 9 (irf9) in common carp Cyprinus carpio: a pivotal molecule in the Ifn response against pathogens

“…Both PBLs and HKLs consist of heterogeneous cells and are widely used as an experimental system to study immune responses (Li et al, ; Zhang et al, ; Zhang et al, ). We isolated the leukocytes from peripheral blood and head kidney for further investigation to obtain a better understanding of the antimicrobial role of irf9 .…”